This invention relates to improved opacified latex emulsion paints. Latex paints are very popular due to their coating effectiveness, opacifying properties, and their ease of application. For example, SPRED SATIN, a trademark of SCM Corporation, identifies a typical latex emulsion paint. Conventionally opacified latex emulsion paints generally include in an aqueous dispersion: water, opacifying pigment, filler pigment, aqueous compounded film-forming latex, usually bodying agents, and dispersing assistants. Other conventional latex paint ingredients can include, for example, pesticides, odorants, flow control agents, bubble breakers, defoamers, plasticizers, adhesion promoters, coalescing solvents, tinting agents, anti-freeze agents, and pH buffers. Numerous specialty latex paints are known, such as disclosed in Ramig application Ser. No. 345,301 filed Mar. 27, 1973, now abandoned; U.S. Pat. No. 3,280,030; U.S. Pat. No. 3,447,940; British Pat. No. 811,425, and the same are incorporated herein by reference.
Most conventional opacified latex emulsion paints rely primarily on titanium dioxide as an opacifying pigment. It now has been found that substantial opacification is achieved by the inclusion of porous synthetic magnesium silicate as an opacifying pigment whereby excellent opacification can be achieved without conventional TiO.sub.2 opacifying pigment. The opacification achieved in the latex paint of this invention by the inclusion of the porous magnesium silicate is particularly surprising since standard non-porous magnesium silicates have little or no opacifying properties when used in conventional oil-based paints typically referred to as alkyd paints.
Accordingly, it is a primary object of this invention to provide an improved opacified emulsion latex paint containing porous synthetic magnesium silicate as an opacifying pigment whereby TiO.sub.2 can be partially or completely eliminated. Improved opacity can be achieved without diminishing other physical properties of paint films.
These and other advantages of this invention will become more apparent by referring to the Detailed Description of the Invention.